----- "stephen mulcahy" <[EMAIL PROTECTED]> wrote: > As a further aside, some MPI libraries (OpenMPI comes to mind) seem to > make some efforts to keep processes on the same cores also (or can be > instructed to via a run-time option).
At one point MVAPICH2 would enable this by default on AMD Opteron - but always started from core 0 when binding processes. So if you had an 8 core box and 2 x 4 CPU jobs were run on it they'd both end up fighting over cores 0-3 whilst cores 4-7 sat in a corner twiddling their thumbs and wondering why they had no work to do. :-( It got even worse if you launched 4 x 2 CPU jobs.. -- Christopher Samuel - (03) 9925 4751 - Systems Manager The Victorian Partnership for Advanced Computing P.O. Box 201, Carlton South, VIC 3053, Australia VPAC is a not-for-profit Registered Research Agency _______________________________________________ Beowulf mailing list, [email protected] To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf
